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And remember before we all get crazy about MB ... They are Chrysler now!!!!
There's a lot more costs involved than you listed. You haven't factored in warranty costs that the manuf. has to absorb. I bet a $40,000 car only has less than $5000 in raw materials costs, so what's the difference?
As far as cost of metal goes that make be right, but look at all the casting, machining, forming, etc
Let's not forget the hot tubs that are directly connected to the stock market by way of their parent companies. Hot Spring for example, they are always under pressure to squeeze out maximum profits while keeping expenses as low as possible. Great for the stockholder, not so great for the average consumer.